#include<stdio.h>

int sum(int s,int e)
{
	int result=0;
	for(int i=s;i<=e;i++)
	{
		result+=i;
	}
	return result;
}

int main()
{
	int start=1;
	int end=100;
	printf("I will begin\n");
	int n=sum(start,end);
	printf("running done,result is:[%d-%d]=%d\n",start,end,n);
	return 0;
}
